The present invention relates to a label, particularly for use in in-mold applications, having one or more removable portions. The removable portion(s) may be used to carry indicia such as coupons, proofs-of-purchase or contest pieces, whose use has become popular in labeling a wide variety of items and containers.
One of the problems faced in designing labels with removable portions is to provide for the removable portion to be attractive and legible as well as easily and neatly removable. In most labeling environments, it is desirable to have both the removable portion and the balance of the label remain flat against the labelled surface to maximize legibility and make the labelled surface or container more attractive. Also, it is preferred to allow a portion of the removable portion to be easily grasped by the person desiring to remove the removable portion. Accordingly, it is desirable to provide an unadhered tab portion on the removable portion which can be easily grasped and pulled to effect removal.
In removing the label's removable portion, it is most advantageous to provide a means to allow the removable portion to be easily and cleanly taken from the labelled surface. This is important so that one removing such portion can do so with little effort and without mutilating the removable portion or disturbing the indicia either on the removable portion or the remaining balance of the label. More specifically this involves providing a removable portion whose adhesion to the underlying surface and attachment to the balance of the label will not exceed the tear modulus or the elastic limit of the label material upon removal.
Another problem associated particularly with in-mold labels is to provide all of the above advantages in a label amenable to in-mold application. Some of the particular obstacles include maintaining the appropriate characteristics in such a label to allow it to comport to the various physical and thermal requirements of adhesion to a given molded container or product. These characteristics include the proper degree of adhesion for the removable portion, its tab and the balance of the label, and the appropriate coshrinkage between the entire label and the molded surface to which it is applied. Also, the control of adhesion and coshrinkage prevents blistering and puckering which results in a label that may be insecurely attached and/or illegible.
An example of an in-mold label of the prior art is disclosed in U.S. Pat. No. 4,587,158 issued to Ewing on May 6, 1986 and reissued as U.S. Reissue Pat. No. Re. 32,929 issued May 23, 1989, and Japanese Patent Application No. 56-169117 by Yasuda filed Oct. 22, 1981 and published Apr. 25, 1983, which are hereby incorporated herein by reference.
In accordance with the above characteristics and desired advantages, the present invention provides a label having at least one removable portion which can be easily and cleanly removed, and which provides for clear display of indicia on both the permanent and removable portion both before and after removal of the removable portion. The present invention also makes these advantages available to a label applied in an in-mold setting.